Comprehensive surveys of upland hay meadows in the North Pennines were undertaken in the early 1980s by the NCC (Nature Conservancy Council). More recently, the Hay Time project undertook surveys of a large number of upland hay meadows in the North Pennines. This was the most comprehensive survey of upland hay meadow vegetation in the area since the NCC survey.
This large volume of data gave the opportunity to conduct a detailed analysis of the current composition of upland hay meadow vegetation. It also allowed some comparisons to be made with a similar-sized dataset from roughly 25 years earlier.
These analyses help to clarify some current grey areas relating to the diversity of upland hay meadow vegetation. Several types of species-rich upland hay meadow vegetation that are currently poorly described and/or understood are described in some detail. These data will help to broaden the technical definition of the upland hay meadows UKBAP priority habitat.